Pneumatic-electric self-lapping control apparatus

ABSTRACT

This invention relates to an electro-pneumatic self-lapping unit of a brake valve for use on a railway locomotive to effect control of the pressure in a train line pipe by effecting appropriate energization and deenergization of release and application magnet valve devices provided on the locomotive and each car in a train for supplying fluid under pressure locally to the train line pipe and releasing fluid under pressure therefrom. The energization and deenergization of these magnet valve devices is controlled via train wires by mechanically actuated switches selectively operated substantially simultaneously with the selflapping unit on the locomotive to supply fluid under pressure to or release fluid under pressure from the train line pipe in response to the engineer effecting manual rotation of a handle mounted on the same shaft as a cam the rotation of which controls operation of the self-lapping unit.

United States Patent [4 1 Mar. 21, 1972 McClure et al.

[54] PNEUMATIC-ELECTRIC SELF- LAPPING CONTROL APPARATUS [72] Inventors: Glenn T. McClure, McKeesport; Robert B.

Salton, Pittsburgh, both of Pa.

[73] Assignee: Westinghouse Air Brake Company, Wilmerding, Pa.

[22] Filed: Jan. 5, 1970 [2]] Appl. No.: 765

[S2] U.S. Cl ..303/15, 303/3, 303/20 [51] Int. Cl. ..B60t 13/66 [58] Field of Search ..303/3,4,l0, 15,17, 20, 35, 303/36 [56] References Cited UNITED STATES PATENTS 2,937,906 5/1960 May ..303/20 X 3,275,382 9/1966 Worbois ..303/15 Primary ExaminerDuane A. Reger Attorney-Ralph W. Mclntire, Jr.

[5 7 ABSTRACT This invention relates to an electro-pneumatic self-lapping unit of a brake valve for use on a railway locomotive to effect control of the pressure in a train line pipe by effecting appropriate energization and deenergization of release and ap plication magnet valve devices provided on the locomotive and each car in a train for supplying fluid under pressure lo- 30 Claims, 5 Drawing Figures LOCOMOTIVE JHQQBRAKE PIPE APPLICATION WIRE RELEASE WIRE} RETURN WIREJ Pater lted March 21, 1972 3,650,572

4 Sheets-Sheet 1 COMPRESSOR |6 3 62 I4 88 -|7 I 4 PM Lg |5- J j j 1-|09BPAKE PIPE 0/ 3 94% APPLICATION WIRE) 0/ H2 RELEASE WIRE) "JLOCOMGTIVE ETURN WIRE) H3 H4 H2 INVENTOR. GLENN T. M CLURE ROBERT BSALTON yway. WZMMZ J/ ATTORNEY,

Patented March 2 1, 1972 4 Sheets-Sheet 2 ATTORNEY Patented March 21, 1972 4 Sheets-Sheet 5 INVENTOR. GLENN T M CLURE ROBERT B. SALTON ATTORNEY Patented March 21, 1972 3,650,572

4 Sheets-Sheet 4 IMIIIMIWWWH I IA US l I l 5 INVENTOR. GLENN TM 'CLURE ROBERT BSALTON ATTORNEY PNEUMATIC-ELECTRIC SELF-LAPPING CONTROL APPARATUS BACKGROUND OF THE INVENTION Electro-pneumatic brake systems comprising pneumatically operated master controller switch devices for controlling the electrical train line wire circuits of electromagnet valves on the cars in the train so as to effect variations of pressure in the train line pipe have been known in the railway braking art for many years. U.S. Pat. No. 1,185,738 issued June 6, 1916, to Walter V. Turner and assigned to the assignee of the present application discloses such a system. However, this Turner patent merely discloses an electromagnet valve for releasing fluid under pressure from a train brake pipe without any electromagnet valve means for supplying fluid under pressure to the brake pipe for effecting the charging thereof to effect a brake release. Moreover, there are many forms and designs of fluid pressure operated master controller switch devices known in the baking art. However, it has been found that in actual practice these fluid pressure operated master controller switch devices tend to be sluggish in operation which causes undesirable arcing at and consequent pitting of their electrical contacts. This, in turn, has resulted in chattering of the magnet valves thereby causing rapid wear of the respective valves and their corresponding valve seats.

The above-mentioned sluggish operation of fluid pressure operated master controller switch devices when used in an electro-pneumatic automatic brake system results in overcasting of pressure changes and consequent pumping action until a balanced pressure condition is achieved. More specifically, the delayed opening of the contacts causes the reduction of the pressure in the train brake pipe and on one side of an abutment that operates the switch device to exceed, that is overcast, the reduction of the pressure previously manually effected, by operation of the brake valve device, in the equalizing reservoir and on the opposite side of this abutment. Such undesired overcasting thereafter causes undersired reclosing of the release contacts to effect energization of the release electromagnet valves which in turn cause the supply of fluid under pressure to the train brake pipe. This buildup of pressure in the train brake pipe results in an undesired partial release of the brakes and also in an increase in the fluid pressure acting on the one side of the abutment thereby effecting reclosing of the application contacts whereupon the abovedescribed cycle is repeated. This undesired cycling is termed pumping. Furthermore, brake pipe leakage reduces the fluid pressure on the one side of the abutment which in turn effects respective operation of the master'controller switch devices to maintain the desired pressure. When fluid pressure operated master controller switch devices are used in an electro-pneumatic straight-air brake system similar undesired results are obtained.

Accordingly, it is the general purpose of this invention to provide an improved electro-pneumatic brake control apparatus having an engineers brake valve that includes a pneumatic self-lapping control valve unit and a master controller switch device for controlling respectively the energization and the deenergization of an application train wire and a release train wire extending through the cars in a train, the selflapping valve unit and the switch device being so interlocked via a mechanical linkage that operation of the self-lapping unit leads the operation of the switch device in a manner to eliminate cycling or pumping action of the switch device.

SUMMARY OF THE INVENTION According to the present invention, energization and deenergization of an application and a release magnet valve device on each vehicle in a train is effected respectively via a corresponding one of a pair of train wires accordingly as a rockable arm, constituting one contact of a pair of switches for controlling the power supply to these wires, is mechanically actuated to effect closing of one of the pair of switches by a mechanical linkage so interlocked with a pneumatic selflapping control valve unit that rotation of a single cam on a brake valve handle shaft so operates the self-lapping unit and one or the other of the pair of switches that the self-lapping unit is operable to effect a variation of fluid pressure in a train line pipe slightly prior to operation of the magnet valve devices to effect a corresponding variation of pressure in the train line pipe.

The brake apparatus constituting the present invention is rendered fail-safe in that upon failure of either the self-lapping unit or the switch device, the other is operative to effect varia tions of pressure in the train line pipe to thereby control the brakes on all the vehicles comprising the train.

In the accompanying drawings:

FIG. 1 is a block and line diagram of an electro-pneumatic automatic railway train brake system embodying the invention.

FIG. 2 is a plan view of a combined pneumatic self-lapping control valve unit and a master controller switch device'that is embodied in an engineers brake valve illustratively shown as a rectangular block in FIG. 1.

FIG. 3 is a vertical cross-sectional view, taken along the line 3-3 of FIG. 2 and looking in the direction of the arrows, showing structural details of the pneumatic self-lapping control valve unit and master controller switch device shown in FIG. 2.

FIG. 4 is a left-hand end view of the combined control valve unit and master controller switch device shown in FIG. 2 with the cam, the cam roller and the lever member in which the roller is pivotally mounted omitted.

FIG. 5 is a right-hand end view of the combined control valve unit and switch device shown in FIG. 2.

Referring to FIG. 1 of the drawings, the electro-pneumatic automatic railway train brake system embodying the invention comprises a brake cylinder 1 provided on the locomotive and each car in the train, a plurality of reservoirs including on the locomotive a main reservoir 2 and an equalizing reservoir 3, and on both the locomotive and each car in the train an auxiliary reservoir 4, a brake pipe 5 that extends from end to end of the locomotive and thence through all the cars in the train, an engineers brake valve 6 such as that disclosed in U.S. Pat. No. 2,958,561, issued Nov. 1, 1960 to to Harry C. May and assigned to the assignee of the present application except that the self-lapping control valve device 14 shown in this patent is replaced by a self-lapping control valve device that is interlocked with a pair of switches by a mechanical linkage in a manner hereinafter described, whereby these switches are operative to control the energization and deenergization of an application train wire 7 and a release train wire 8 each extending from one end of the locomotive and thence through all the cars in a train, a return train wire 9 also extending from one end of the locomotive and thence through all the cars in the train, and on both the locomotive and each car and application magnet valve device 10 and a release magnet valve device 11, which are connected respectively between the application train wire 7 and the return train wire 9, and between the release train wire 8 and the return train wire 9 which on the locomotive is connected by a wire 12 to the negative terminal of a source of electrical power which may be, for example a storage battery 13.

Additional components of the electro-pneumatic automatic railway train brake system shown in FIG. 1 include on the locomotive and each car in the train a pneumatically operated brake control valve 14 each of which is connected to the brake pipe 5 by a branch pipe 15. These brake control valves 14 are operable upon an increase in the pressure in the brake pipe 5 to a normal chosen pressure to effect charging of the corresponding auxiliary reservoir 4 to this normal chosen pressure and the release of the brakes on the respective vehicle, and operable upon a reduction of pressure from this normal chosen pressure to effect the supply of fluid under pressure from the auxiliary reservoir 4 to the brake cylinder 1 on the respective vehicle to cause a brake application to a degree corresponding to this reduction.

The brake valve 6 comprises a relay valve device the construction and operation of which may be identical to that of the relay valve device 13 shown in the above-mentioned U.S. Pat. No. 2,958,561. Briefly, this relay valve device is operable to effect the supply of fluid under pressure from a supply chamber (not shown), which is connected by a passageway (not shown), and a corresponding pipe 16 to the main reservoir 2, to a delivery chamber (not shown), which is connected by a passageway (not shown) and a corresponding pipe 17 to the brake pipe 5.

The brake valve 6 further comprises a combined pneumatic self-lapping control valve unit and master controller switch device 18 the details of which are shown in FIGS. 2 to 5, inclusive, of the drawings, operable upon movement ofa handle 19 (FIG. 1) of the brake valve 6 to its release position to effect charging of the equalizing reservoir 3 on the locomotive and the brake pipe to a desired normal full charged value in a manner hereinafter described in detail.

The combined pneumatic self-lapping control valve unit 7 and master controller switch device 18 comprises a pneumatic self-lapping control valve unit 20, the details of construction of which are best shown in FIG. 3, a master controller switch mechanism 21 and a mechanical linkage 22 interlocking the control valve unit 20 and the master controller switch device 21 in order that the engineer may effect, by manual rotation the handle 19 of the brake valve 6, substantially simultaneous operation of the control valve unit 20 on the locomotive and the magnet valve devices and 11 on both the locomotive and cars via the switch device 21 and train wires 7, 8 and 9 to effect variations of the pressure in the brake pipe 5 thereby to 1 control the application and the release of the brakes on the train.

The handle 19 shown in FIG. 1 and a cam 23 shown in FIG. 2 and suitable mounted on a common shaft 24 which is journaled in bearings (not shown) carried by the casing of the brake valve 6. Rotation of the cam 23 by the handle 19 effects operation of the self-lapping control valve unit which will now be described in detail.

The self-lapping control valve unit 20 shown in detail in FIG. 3 of the drawings comprises a diaphragm 25 the outer periphery ofwhich is clamped between a main casing section 26 and a cover member 27 that is secured to the main casing section 26 by a plurality of cap screws 28 one of which appears in FIG. 3.

The inner periphery of the diaphragm 25 is clamped between a combined diaphragm follower and exhaust valve seat member 29 and an annular diaphragm plate 30 through which a screw-threaded stem 31 integral with the exhaust valve seat member 29 extends to receive a screw-threaded cap nut 32 which is tightened against the diaphragm plate 30 it being noted that the cap nut 32 is provided with a plurality of ports 33 opening into the interior thereof.

The above-mentioned combined diaphragm follower and exhaust valve seat member 29 of the self-lapping control valve unit 20 is provided with a bore 34 and a coaxial counterbore 35 the bore 34 having an annular valve seat 36 formed at the left-hand end thereof.

The combined diaphragm follower and exhaust valve seat member 29 is provided on its left hand end with a cylindrical skirt portion 37 that is slidably guided in a corresponding counterbore 38 that is coaxial with a bore 39 provided in a bushing 40. that is press-fitted into a bore 41 that extends through the main casing section 26. The right-hand end of the bore 41 opens into a chamber 42 formed by the cooperative relationship of the diaphragm 25 and the main casing section 26.

Sealingly and slidably mounted in the counterbore 38 on the left-hand side of the skirt portion 37 of the combined diaphragm follower and exhaust valve seat member 29 is a supply valve seat piston member 43 that is provided with three spaced-apart peripheral annular grooves in each of which is disposed in an O-ring 44 that forms a seal with the wall surface of the counterbore 38 to prevent flow of fluid under pressure between the periphery of the supply valve seat piston member 43 and the wall of the counterbore 38. The supply valve seat piston member 43 is also provided with a bore 45 and a coaxial counterbore 46 the left-hand end of which is provided with internal screw threads. The supply valve seat piston member 43 is also provided with two spaced apart cross-bores 47 and 48, the cross-bore 47 intermediate its ends opening into the counterbore 46 and at its opposite outer ends onto a first peripheral annular groove 49 formed on the supply valve piston seat member 43 between the center O-ring 44 and the left-hand O-ring 44. The cross-bore 48 intermediate its ends opens into the bore 45 and at its opposite outer end onto a second peripheral annular groove 50 formed on the piston member 43 intermediate the center O-ring 44 and the righthand O-ring 44. The supply valve seat piston member 43 has an annular supply valve seat 51 formed at the left hand of the bore 45 therein. I

The internal screw threads formed at the left-hand end of the counterbore 46 have screw-threaded engagement with external screw threads formed on the right-hand end of a pusher member 52 the right-hand end of which is provided with a bottomed bore 53 between the left-hand end of which and a supply valve 54 is interposed a spring 55 for normally biasing the supply valve 54 against the supply valve seat 51. Formed integral with the supply valve 54 is a stem 54a that is fluted for a part of its length. The stem 54a extends through the bore 45 and at its right-hand end abuts an exhaust valve 56 which, as shown in FIG. 3, is seated on the exhaust valve seat 36. The fluted portion of the stem 54a provides that when the valve 54 is unseated from the supply valve seat 51, fluid under pressure may flow from a supply valve chamber 57 formed in the main casing section 26 to a delivery chamber 5.8 also formed in this casing section via a first set of arcuately spaced ports 59 in the bushing 40, peripheral annular groove 49, cross-bore 47, counterbore 46, past the supply valve seat 51, bore 45, crossbore 48, peripheral groove 50, and a second set of arcuately spaced ports 60 provided in the bushing 40. Fluid under pressure is supplied from the main reservoir 2 to the supply valve chamber 57 via the hereinbefore-mentioned pipe 16 and a corresponding passageway formed in the casing section 26. The delivery chamber 58 is connected by a passageway and corresponding pipe 61 to the hereinbefore-mentioned equalizing reservoir 3.

As shown in FIG. 1 of the drawings, connected to the pipe 61 intermediate the ends thereof is one end of a pipe 62 that is connected by a corresponding passageway (not shown) in the brake valve 6 which passageway opens into a chamber at one side ofa diaphragm ofa relay valve device of this brake valve 6 as is shownand described in hereinbefore-mentioned U.S. Pat. No. 2,958,561.

As shown in FIG. 3, the left-hand end of the pusher member 52 is provided with a headed wear pin 63 that, as shown in FIG. 2 of the drawings, abuts a cam surface 64 formed on a lever member 65 that at its upper end is pivotally mounted on a pin 66 carried by a clevis 67 formed at one end of an arm 68. As best shown in FIG. 3 of the drawings, arm 68 is secured to a bracket 69 that in turn is attached to the main casing section 26 by a pair of cap screws 70.

As can be seen from FIGS. 2 and 3, the lever member 65 has formed integral therewith a clevis between the jaws of which is disposed a roller 71 that is rotatably mounted on a headed pin 72 carried by these jaws it being noted that this roller 71 abuts the hereinbefore-mentioned cam 23.

Referring to FIG. 3 of the drawings, it will be noted that disposed in the counterbore 35 formed in the stem 31 is a spring seat 73 that at one side abuts the end of a fluted stem that is formed integral with the exhaust valve 56 and is disposed in the bore 34 in the combined diaphragm follower and exhaust valve seat member 29. Interposed between the other side of this spring seat 73 and the cap nut 32 is an exhaust valve spring 74 that is effective to unseat exhaust valve 56 from its seat 36 in a manner hereinafter explained.

As shown in FIG. 3, the cover member 27 is provided with an internal screw-threaded bore 75 for receiving an annular screw-threaded adjusting screw 76 against the left-hand end of which rest a double spring seat 77. A heavy control spring that is stronger than the spring 55 is interposed between the spring seat 77 and the diaphragm plate 30 it being understood that while the various elements of the self-lapping control valve unit occupy the position shown in FIG. 3 this spring 78 is compressed since these elements of the control valve unit 20 are shown in the position they occupy upon moving to a lap position subsequent to effecting charging of the equalizing reservoir 3 (FIG. 1) to the desired fully charged pressure normally carried therein while the brakes on the train are released.

Slidably mounted in the annular adjusting screw 76 is a rod 79 that is provided at its right-hand end and exterior of the cover member 27 with a clevis 80 and at its left-hand end with a collar 81 that is biased against the cap nut 32 by a spring 82 any suitable means to the upper end of a hollow rod 87.

Disposed in the hollow rod 87 is a wire 88 that at its upper end is secured, as for example, by soldering to the metallic U- shaped clip member 84 and is covered with a suitable insulat ing covering. As shown in FIGS. 4 and 5, the wire 88 extends through the hollow rod 87 to the exterior thereof and is connected to the positive terminal of the storage battery 13, as shown in FIG. 1.

As shown in FIG. 2, disposed on the left-hand side of the movable contact 83 so as to be in the path of movement thereof is a release contact 89 that is formed as the head ofa bolt 90 that extends through a bore (not shown) in the upper end ofa lever 91 and a washer 92. The threaded end of bolt 90 receives a nut 93 between which and the washer 92 is clamped one end ofa wire 94 that extends through the brake valve 6 to the exterior thereof and at its opposite end is connected to the release train wire 8 as shown in FIG. 1.

The lever 9lis rockably mounted on a pin 95 the opposite ends of which are anchored in a pair of spaced-apart arms 96 only one of which appears in FIG. 2. These arms 96 are formed integral with an angle bracket 97 that is secured to a plate member 98 constructed of some suitable insulating material by any suitable means such as, for example, a pair of cap screws. The plate member 98 is provided at its right-hand end, as viewed in FIG. 2, with a pair ofbosses 99 each having a smooth bore therein through which extends a cap screw 100 that has screw-threaded engagement with an internal screwthreaded bore provided in a flat plate 101. As shown in FIG. 5, this flat plate 101 is mounted on the cover member 27 by two of the four cap screws 28 that secured this cover member to the main casing section 26.

As shown in FIG. 2, the lower end of the lever 91 is biased against a first adjustable stop in the form of a set screw 102 that is carried in a screw-threaded boss 103 which is integral with the angle bracket 99 by a conical spring 104 interposed between the lever 91 and the angle bracket 97. The lever 91 and release contact 89 carried thereby may be rocked counterclockwise about the pin 95 against the yielding resistance of the spring 104 by the movable contact 83 until a boss 105 with the with lever 91 strikes the end ofa second adjustable stop in the form ofa set screw 106 that is carried in a screw-threaded bore provided therefor in the angle bracket 97.

Disposed on the right-hand side of the movable contact 84 so as to be in the path of movement thereof is an application contact 107 that is formed as the head ofa bolt 108. This bolt is carried in the upper end of a lever that is identical to the lever 91 and is rockably mounted in the same manner as the lever 91. Accordingly, this lever, the angle bracket on which it is rockably mounted, the stops and biasing spring therefor,

and the cap screws securing this angle bracket to the plate member 98 are denoted by the same numerals with the addition of the suffix a. i

A wire 109, one end of which is clamped between the washer 92a and the nut 93a, extends through the brake valve 6 to the exterior thereof and at its opposite end is connected to the application train wire 7, as shown in FIG. 1.

The movable contact 83 is moved into and out of circuit closing contact with the stationary release contact 89 to effect energization and deenergization of the release train wire 8 and the solenoid of each release magnet valve device 11, or the movable contact 84 is moved into and out of circuit closing contact with the stationary application contact 107 to effect energization and deenergization of the application train wire 7 and the solenoid of each application magnet valve device 10, by operation of the mechanical linkage 22 which will now be described in detail.

As shown in FIGS. 4 and 5 of the drawings, the lower end of the hereinbefore-mentioned hollow rod 87 is disposed, as by a press-fit, in a bore 110 (FIG. 4) provided in an offset arm 111 that is formed integral with and adjacent oneend a hollow hub 112 that is rockably mounted on a fulcrum pin 113. As best shown in FIG. 4, the hub 112 is disposed between the jaws ofa clevis 114 in which the opposite ends of the fulcrum pin 113 are anchored. This clevis 114 is secured to the hereinbeforementioned flat plate 101 by a pair of spaced-apart cap screws 115.

As can be seen from FIG. 4, the hub 113, in addition to the offset arm 111, has formed internal therewith a pair of spacedapart and oppositely extending arms 116 and 117. The arm 116 is operatively connected to one end of an adjustable rod 118 by a pin 119 that extends through a bore formed in this arm adjacent its outer end and has its opposite ends journaled in the jaws ofa clevis 120 provided on the left-hand end of rod 118 as shown in FIGS. 2 and 4.

As can be seen from FIG. 2, the rod 118 extends through a bore 121 provided in the hereinbefore-mentioned clevis 114 and a coaxial bore 122 oflarger diameter in the flat plate 101. Adjacent its right-hand end, the rod 1.18 is provided with external screw threads for receiving a nut 123 against the left hand side of which rest a spring seat 124 between which and the flat plate 101 is interposed a spring 125 that is disposed in surrounding relation to the rod 118. The purpose of the spring 125, the strength of which is less than that ofspring 82, is to always bias the offset arm 111 and hollow rod 87 in a clockwise direction, as viewed in FIG. 2, and thereby compensate for any wear that occurs at the several pivotal connections between the various links and levers comprising the mechanical linkage 22.

As can be seen from FIGS. 2 and 4, the lower end of arm 116 is disposed between the jaws ofa clevis 126 formed at the right-hand end of a link 127 and operatively connected thereto by a pin 128 the opposite ends of which are anchored in this clevis. The link 127 has formed at its left-hand end a clevis 129 between the jaws of which is disposed the lower end of a lever 130 that is operatively connected to the link 127 by a pin 131 that has its opposite ends anchored in this clevis 129.

As can be seen from FIGS. 2 and 3, the lever 130 extends through a rectangular-shaped slot 132 provided in the hereinbefore-mentioned pusher member 52 of the control valve unit 20, and has a 1ost-motion connection therewith which will now be described.

As can be best seen from FIG. 3, the pusher member 52 is provided with an elongated slot 133 the axisof which is at an angle of 90 to the axis of the rectangular slot 132. A headed pin 134 extends through the elongated slot 133, and a bore 135 in the lever 130 and is provided with a peripheral groove in which is inserted a snap ring 136 which prevents removal of this pin since it will be understood that the outside diameter of snap ring 136 is greater than the width of the elongated slot 133. It will be understood from FIGS. 2, 3 and 4 that the spring 125 is effective via rod 118, pin 119, arms 116 and 117 which are integral with hub 112, link 127, pins 128 and 131,

and lever 130 to bias the pin 134 toward or against the lefthand end of the slot 133.

As shown in FIG. 2, the upper end of the lever 130 is disposed between the jaws of a clevis 137 formed at the lefthand end of a U-shaped link 138 and operatively connected thereto by a pin 139 that has its opposite ends anchored in the jaws of this clevis 137.

The right-hand end of the U-shaped link 138 is provided with a clevis 140 between the jaws of which is disposed the upper end of a lever 141 that is operatively connected to the link 138 by a pin 142 that has its opposite ends anchored in the jaws of this clevis 140.

As can be seen from FIG. 2, the lever 141 is disposed between the jaws of the clevis 80 and operatively connected thereto by a pin 143 that has its opposite endsjournaled in this clevis. The lower end of the lever 141 is disposed between the jaws ofa clevis 144 formed on the right-hand end ofa link 145 and operatively connected to this clevis 144 by a pin 146 that has its opposite ends journaled in the jaws thereof.

The left-hand end of the link 145 is provided with a clevis 147 between the jaws of which disposed the end of an eye bolt 148 that is operatively connected to the link 145 by a pin 149 that has its opposite ends anchored in the jaws of the clevis 149. The threaded portion of the eye bolt 148 has screwthreaded engagement with the internal screw threads of a screw-threaded bore (not shown) provided in the flat plate 101. A pair of lock nuts 150 and 151 carried by the eye bolt 148 provide for locking it in any adjusted position relative to the flat plate 101.

In order to secure the main casing section 26 to the body of the brake valve 6, this casing section 26 has formed integral therewith a bolting flange 153 (FIGS. 2, 4 and provided with four bores 154 (FIG. 2) for receiving cap screws (not shown) which have screw-threaded engagement with screwthreaded bores (not shown) provided in the body of the brake valve.

As shown in FIG. 1 of the drawings, the positive terminal of the application magnet valve device on the locomotive and each car in the train is connected to the application train wire 7 by a wire 155 and the negative terminal of each of these application magnet valve devices 10 is connected to the return wire 9 by a wire 156. Also, as shown in FIG. 1, the positive terminal of the release magnet valve device 11 on the locomotive and each car in the train is connected to the release train wire 8 by awire 157 and the negative terminal of each of these release magnet valve devices 11 is connected by a wire 158 to the corresponding wire 156 which, as aforestated, is connected to the return train wire 9.

In order for the release magnet valve device 11 on the locomotive to effect the supply of fluid under pressure to the brake pipe 5, an inlet port of this valve device is connected by a pipe 159 to the hereinbefore-mentioned pipe 16 intermediate the ends thereof which pipe 16 is connected to the main reservoir 2, and a delivery port of this valve device 11 is connected by a pipe 160 to the brake pipe 5. Furthermore, in order for the release magnet valve devices 11 on the cars in the train to effect the supply of fluid under pressure to the brake pipe 7, the inlet port of each of these valve devices 11 is connected by a pipe 61 to a supply reservoir (not shown) on the respective car and charged with fluid under pressure in any suitable manner, and the corresponding delivery port is connected by a pipe 162 to the brake pipe 5.

In order for the application valve device 10 on each car to effect the release of fluidunder pressure from the brake pipe 5 to atmosphere, an inlet port of the valve device 10 is connected by a pipe 163 to the pipe 162, and the outlet port is open to atmosphere.

To initially charge the brake apparatus shown in FIG. 1 of the drawings, diesel engines are started for operating fluid compressors (not shown) to effect charging of the main reservoir 2.

It may be assumed that the handle 19 (FIG. 1) of the brake valve 6 is in its release position. Therefore, the cam 23 will occupy the position shown in FIG. 2.

Prior to charging the main reservoir 2, no fluid under pressure will be present in the self-lapping control valve unit 20. Under this condition the spring 78 (FIG. 3) is effective to bias the combined diaphragm follower and exhaust valve seat member 29 against a pair of stops 260 (FIG. 3) formed integral with the casing section 26. Also, the strength of the springs 55 and 74 are such that, under the conditions described above, the exhaust valve 56 is seated on its seat 36 and the supply valve 54 is unseated a maximum amount from its seat 51.

As the main reservoir 2 is charged, fluid under pressure will flow therefrom to the equalizing reservoir 3 via pipe and passageway 16, chamber 57, ports 59, groove 49, cross-bore 47, counterbore 46, past unseated supply valve 54, bore 45, cross-bore 48, groove 50, ports 60, chamber 58 and passageway and pipe 61, it being noted that some of the fluid under pressure supplied to the chamber 58 flows therefrom to the chamber 42 via a small passageway 164 provided in the casing section 26 which passageway constitutes a choke the size of which determines the rate of flow of fluid under pressure to the chamber 42.

Fluid under pressure thus supplied to the equalizing reservoir 3 flows therefrom to the relay valve device of the brake valve 6 in the manner described in the hereinbefore-mentioned U.S. Pat. No. 2,958,561 to cause operation of this relay valve device to effect the supply of fluid under pressure from the main reservoir 2 to the brake pipe 5.

With the cam 23 in the release position shown in FIG. 2, the mechanical linkage 22 is effective to cause the movable contact 83 to engage the release contact 89. This establishes a power supply circuit to cause energization of the solenoid of the release magnet valve device 11 on the locomotive and each car in the train. This power supply circuit extends from the positive terminal of the battery 13 (FIG. 1) via wire 88, U- shaped clip member (FIG. 2), movable contact, 83, release contact 89, wire 94, release train wire 8 (FIG. 1), a wire 157 to the positive terminal of the solenoid of each release magnet valve device 11, thence via the winding of the respective solenoid to the negative terminal thereof, a wire 158, a wire 156, return train wire 9 and wire 12 to the negative terminal of the battery 13.

Accordingly, it will be understood that the release magnet valve devices 11 now operate to effect the supply of fluid under pressure from the main reservoir 2 on the locomotive and the supply reservoirs on the cars in the train to the train brake pipe 2 simultaneously as the relay valve device of the brake valve 6 operates to effect the supply of fluid under pressure to the train brake pipe.

As fluid under pressure is supplied to the equalizing reservoir 3 (FIG. 1) and the chamber 42 (FIG. 3) in the manner explained above, the pressure in this chamber 42 is increased. Since the left-hand side of the diaphragm 25 is subject to the pressure in the chamber 42, when the pressure in this chamber is increased sufficiently to overcome the resistance of the control spring 78, the diaphragm 25 will be deflected in the direction of the right hand against the yielding resistance of the control spring 78. As the diaphragm 25 is thus deflected in the direction of the right hand, the combined diaphragm follower and exhaust valve seat member 29 having formed integral thereon the exhaust valve seat 36 is likewise moved in the direction of the right hand whereupon the spring 55 is rendered effective to move the supply valve 54, stem 54a and exhaust valve 56 in the same direction until the supply valve 54 is moved into seating contact with its seat 51 it being understood that this spring 55 maintains the exhaust valve 56 seated on its seat 36 during this movement.

From the foregoing, it is apparent that the increase in pressure in the chamber 42 operates the self-lapping control valve unit 20 to a lap position in which the supply valve 54 is seated on its seat 51 to cut off further flow of fluid under pressure from the main reservoir 2 to the chamber 42 in the control valve unit 20 and to the equalizing reservoir 3.

When the supply of fluid under pressure to the equalizing reservoir 3 is thus cut off, the relay valve device of the brake valve 6 is operated to a lap position to cut off further supply of fluid under pressure to the brake pipe 2 in the manner described in hereinbefore-mentioned U.S. Pat. No. 2,958,561.

Referring to FIGS. 2 and 3, it will be seen that as the diaphragm 25 and the exhaust valve seat member 29 are moved in the direction of the right hand in the manner described above, the nut 32 and rod 79 are likewise moved in the same direction it being noted that the springs 82 and 78 are simultaneously compressed.

Referring to FIG. 2, it can be seen that as the rod 79 is thus moved in the direction of the right hand, it is effective via clevis 80 and pin 143 to rock lever 141 clockwise about the pin 146. Accordingly, it is apparent from FIG. 2 that this clockwise rocking of lever 141 is effective to move the U- shaped link 138 in the direction of the right hand.

It will be apparent from FIGS. 2, 3 and 4 that the spring 125 is effective via rod 118, pin 119, arms 116 and 117 on hub 112, link 127, pin 131 and lever 130 to bias the pin 134 against the left-hand end of the slot 133. Therefore, as the link 138 is moved in the direction of the right hand in the manner described above, it is effective to rock the lever 130 clockwise about the pin 134. As the lever 130 is thus rocked clockwise about the pin 134, it is effective via pin 131, link 127, pin 128, and arm 117 to rock hollow hub 112 about pin 113. Since arm 111 is integral with hub 112, as shown in FIG. 4, it is apparent from FIG. 2 that arm 111, hollow rod 87 and hollow sleeve 86 are now rocked clockwise, as viewed in FIG. 2, to move movable contact 83 out of circuit closing contact with release contact 89. This opens the power supply circuit to the release train wire 8 and the solenoid of the release magnet valve device 11 on the locomotive and on each car in the train whereupon these magnet valve devices 11 operate to terminate the supply of fluid under pressure to the brake pipe 5.

The length of the various links, rods and levers comprising the mechanical linkage 22 are so selected or chosen that operation of the self-lapping control valve unit 20 leads operation of the magnet valve devices 10 and 11 on the locomotive and cars in the train. In other words, the supply valve 54 (FIG. 3), is open or unseated from its seat 51 a chosen amount which, for example, may be 0.002 inch at the time the movable contact 83 (FIG. 2) is moved into circuit closing contact with the release contact 89 to cause energization of the solenoids of the release magnet valve devices 11 to cause operation of these valve devices to effect the supply of fluid under pressure to the brake pipe. From the foregoing, it is apparent that the self-lapping control valve unit 20 starts to supply fluid under pressure to the brake pipe slightly before the release magnet valve devices 11 begin to supply fluid under pressure to this pipe 5.

Since operation ofthe control valve unit 20 leads operation of the magnet valve devices and 11, the supply valve 54 (FIG. 3) will be open, for example, 0.002 inch at the time the movable contact 83 FIG. 2) starts to move away from the release contact 89 to open the circuit to the release valve device 11 to cause operation thereof to cut off further supply of fluid under pressure to the train brake pipe 5.

From the foregoing it is apparent that, upon the beginning of initial charging of the equalizing reservoir 3 and brake pipe 5, the supply valve 54 is unseated from its seat 51 a maximum amount, and the movable contact 83 is in circuit closing contact with the release contact 89, and that, upon the pressure in the equalizing reservoir 3 and brake pipe 5 reaching the desired normal fully charged value, the movable contact 83 starts to move away from the release contact 89 just prior to the supply valve 54 engaging its seat 51 to cut off further supply of fluid under pressure from the main reservoir 2 to the equalizing reservoir 3. Thus the release magnet valve devices 11 are deenergized to cause these valve devices to cut off further charging of the brake pipe Sjust prior to the seating of the supply valve 54 on its seat 51 to cut off charging of the brake pipe by the control valve unit 20.

It will be understood that the brake control valves 14 on the locomotive and cars in the train operate in response to charging of the brake pipe 5 to the normal fully charged pressure carried therein to effect a release of all fluid under pressure from the corresponding brake cylinder 1 and to effect charging of the corresponding auxiliary reservoir 4 to the same pressure as is carried in the train brake pipe 5. The brakes on the locomotive and all cars in the train are now released and the train brake equipment fully charged to the desired pressure.

Let it now be supposed that the engineer desires to effect a brake application on the locomotive and all cars in the train. To do so, he will move the handle 19 of brake valve 6 from its release position to a position in its application zone corresponding to the degree of brake application desired.

As the handle 19 is thus moved toward the desired position in its application zone, the shaft 24 and cam 23 are rotated therewith in a counterclockwise direction, as viewed in FIG. 2 of the drawings. The contour of the cam 23 is such that as it is thus rotated in a counterclockwise direction it moves away from the roller 71.

Referring to FIG. 3 of the drawings, it can be seen that as the cam 23 is moved away from the roller 71', the fluid under pressure present in the counterbore 38 is rendered effective to act on the right-hand end of the supply valve seat piston member 43 and move this member, supply valve 54, stem 54a, plunger member 52 having a slot 133 (FIG. 3) therein, and headed wear pin 63 in the direction of the left hand, as viewed in FIG 3, to thereby rock lever member 65, clockwise as viewed in FIG. 2, about the pin 66 to maintain the roller 71 carried thereby in contact with the cam 23.

As the supply valve 54 and stem 540 (FIG. 3) are moved in the direction of the left hand, in the manner just explained, away from the exhaust valve 56, the spring 74 is rendered effective via the spring seat 73 and the flluted stern of the exhaust valve 56 to unseat this valve 56 from its seat 36, it being understood that the spring 74 is effective to maintain the exhaust valve 56 against the right-hand end of the stern 540.

It will be noted that the equalizing :reservoir 3 is connected to the delivery chamber 58 via pipe and passageway 61, and that the chamber 42 is connected to this chamber 58 by the choked passageway 164. Accordingly, when the exhaust valve 56 is unseated from its seat 36, fluid under pressure will be vented from the equalizing reservoir 3 (FIG. 1) and the chambers 42 and 58 to atmosphere via a plurality of arcuately spaced ports 165 provided in the bushing 40, counterbore 38, past now unseated exhaust valve 5 6, bore 34, counterbore 35, ports 33, the interior of cover member 27 and a pair of ports 166 provided in this cover member.

As fluid under pressure is thus released from the equalizing reservoir 3, it is also released from the relay valve device of the brake valve 6 whereupon this relay valve device operates in the manner described in hereinbefore-mentioned US. Pat. No. 2,958,561 to effect a release of fluid under pressure from the brake pipe 5 to atmosphere.

As fluid under pressure is released from the chamber 42 in the manner explained above, the control spring 78 is rendered effective via the diaphragm plate 30 to deflect the diaphragm 25 in the direction of the left hand, as viewed in FIG. 3, it being understood that the diaphragm plate 30 and nut 32 are simultaneously moved in this direction. Accordingly, fluid under pressure will flow from the equalizing reservoir 3 and chambers 42 and 58 to atmosphere until the exhaust valve seat 36 is moved by spring 78 into seating contact with the exhaust valve 56 to terminate further flow of fluid under pressure to atmosphere. When the flow of fluid under pressure from the equalizing reservoir 3 to atmosphere is thus terminated, the relay valve device of the brake valve is operated to its lap position thereby terminating the release of fluid under pressure from the train brake pipe 5 to atmosphere via this relay valve device.

Referring to FIGS. 2 and 3, when the plunger 52 having slot 133 therein is moved in the direction of the left hand by fluid under pressure acting on the right-hand. end of piston member 43, the left-hand end of the slot 133 starts to move away from the pin 134. This renders spring effective via rod 118 to rock arms 111, 116, and 117 clockwise about pin 113. This clockwise rocking arm 117 is effective via link 127 to rock lever 130 clockwise about pin 139 so that the pin 134 follows plunger 52 and is maintained against the left-hand end of the slot 133 therein as the plunger 52 is moved in the direction of the left hand in the manner hereinbefore described.

It can be seen from FIG. 2 that the above-mentioned clockwise rocking of arm 11 and hollow rod 87 carried thereby is effective to move the movable contact 84 in the direction of the application contact 107. The length of the various links and levers comprising the mechanical linkage 22 may be so selected that, when the exhaust valve 56 is unseated from its seat 36, for example, 0.002 inch, the mechanical advantage provided by this linkage 22 is such as to insure that the movable contact 84 is moved from the position shown in FIG. 2 to the position in which it is in circuit closing contact with the application contact 107.

When the movable contact 84 is thus moved into circuit closing contact with the application contact 107, a power supply circuit is established to cause energization of the solenoid of the application magnet valve device 10 on the locomotive and each car in the train. This circuit extends from the positive terminal of the battery 13 (FIG. 1) via wire 88, U- shaped clip member 85 (FIG. 2), movable contact 84, application contact 107, wire 109, application train wire 7 (FIG. 1), a wire 155 to the positive terminal of the solenoid of each application magnet valve device 10, thence via the winding of the respective solenoid to the negative terminal thereof, a wire 156, return train wire 9 and wire 12 to the negative terminal of the battery 13.

Accordingly, it will be understood that the application magnet valve devices 10 now operate to vent fluid under pressure from the train brake pipe to atmosphere via the respective pipes 160 on the locomotive and 162 on the. cars, a corresponding pipe 167 (FIG. 1) on the locomotive and 163 on the cars, and the respective valve device simultaneously as the relay valve device of the brake valve 6 operates to vent fluid under pressure from the brake pipe 5 to atmosphere.

When the diaphragm (FIG. 3), plate and nut 32 are moved in the direction of the left hand by the spring 78 in response to the release of fluid under pressure from the chamber 42 to atmosphere in the manner explained above, the spring 82 is rendered effective to move the rod 79 in the same direction. Accordingly, it can be seen from FIG. 2 that this movement of the rod 79 in the direction of the left hand is effective via pin 143 to effect counterclockwise rocking of the lever 141 about the pin 146. This counterclockwise rocking of lever 14] is effective via pin 142 to shift link 138 in the direction of the left hand which is effective via pin 139 to rock lever 130 counterclockwise about the pin 134. This counterclockwise rocking of lever 130 is effective via link 127 and pins 131 and 128 to rock arms 117, 116 and 111, hub 112 and hollow rod 87 counterclockwise, as viewed in FIG. 2, about pin 113. It is apparent from FIG. 2 that this counterclockwise rocking of hollow rod 87 is effective to move movable contact 84 out of circuit closing contact with application contact 107. This opens the power supply circuit to the application train wire 7 and the solenoid of the application magnet valve device 10 on the locomotive and each car in the train to terminate venting of fluid under pressure from brake pipe 2 by these valve devices.

It will be understood that the brake control valves on the locomotive and cars in the train operate in response to the reduction of pressure effected in the brake pipe 5 by the relay valve device of the brake valve 6 and also by the application magnet valve devices 10 on the locomotive and cars to effect a brake application on the train to a degree corresponding to the degree of reduction of pressure effected in the brake pipe 5 and then move to their lap position.

The engineer may now effect a partial release of the brakes on the locomotive and cars in the train by rotating the handle 19 from the position it occupies in its application zone toward its release position to another position in its application zone corresponding to the degree of brake application to be retained, or he may effect a complete release of the brakes by returning the handle 19 to its release position.

Since the operation of the self-lapping control valve unit 20, the master controller switch mechanism 21 and the mechanical linkage 21 is the same in effecting either a partial or a complete release of the brakes, it is believed that a description of one will suffice for both, it being understood of course that when a partial release of the brakes is effected, the pressure in the brake pipe 5 is not increased to its normal fully charged chosen pressure as is the case when a complete release is effected. Furthermore, not all of the fluid under pressure in the brake cylinders 1 on the locomotive and cars in the train is released to atmosphere when a partial brake release is effected.

Let it be supposed that the engineer now desired to effect a complete release of the brakes on the locomotive and cars in the train. Accordingly, he will move the handle 19 (FIG. 1) from the position it occupies in'its application zone back to its release position.

As the handle 19 is thus returned to its release position, the shaft 24 and cam 23 are rotated clockwise, as viewed in FIG. 2, until cam 23 occupies the position shown. This clockwise rotation of cam 23 is effective via roller 71 to rock le'ver member 65 counterclockwise about pin 66. Since the cam surface 64 is formed on lever member 65, it is apparent from FIG. 2 that cam surface 64 is moved in the direction of the right hand to effect via headed wear pin 63 simultaneous movement therewith of pusher member 52, pin 134, supply valve seat piston member 43 (FIG. 3) and supply valve seat 51 formed thereon. Since control spring 78 is stronger than spring 55, this spring 55 will not be compressed as the supply valve seat 51 is moved in the direction of the right hand away from the supply valve 54 it being understood that the spring 78 is effective to maintain exhaust valve 56 and supply valve 54 against movement at this time.

Upon movement of supply valve seat 51 away from the supply valve 54 a distance that corresponds to the return of the cam 23 to its release position, fluid under pressure will flow from the main reservoir 2 (FIG. 1) to the equalizing reservoir 3 via pipe and passageway 16, supply valve chamber 57 (FIG. 3), ports 59, groove 49, cross-bore 47, counterbore 46, past now unseated supply valve 54, bore 45, cross-bore 48, groove 50, ports 60, delivery chamber 58 and passageway and corresponding pipe 61. It will be noted from FIG. 3 that some of the fluid under pressure supplied to the chamber 58 flows therefrom to the chamber 42 via choke 164. Accordingly, as fluid under pressure flows to the chamber 42 it will increase the pressure therein to deflect the diaphragm 25 in the direction of the right hand, as viewed in FIG. 3, and move combined diaphragm follower and exhaust valve seat member 29 and exhaust valve seat 36 formed thereon, plate 30, cap nut 32 and rod 79 in this direction against the yielding resistance of springs 78 and 82. It will be understood that as the exhaust valve seat 36 is thus moved in the direction of the righthand, the spring 55 is effective to maintain exhaust valve 56 seated thereon via supply valve 54 and stem 54a and to move the supply valve 54 towards its seat 51. Therefore, it can be seen from the foregoing that fluid under pressure flows from the main reservoir 2 to the equalizing reservoir 3 and to the chamber 42 to increase the pressure therein until the increasing pressure in the chamber 42 moves the exhaust valve seat 36 in the direction of the right hand far enough for the spring 55 to move supply valve 54 into seating contact with its seat 51 thereby terminating flow of fluid under pressure from the main reservoir 2 to the equalizing reservoir 3 and chambers 58 and 42.

Since the cam 23 has been returned to its release position, the equalizing reservoir 3 (FIG. 1) will be charged to the normal fully charged pressure carried therein at the time the supply valve 54 (FIG. 3) is seated on its seat 51 to cut off further flow of fluid under pressure to chamber 42 and the equalizing reservoir.

It will be understood that as the pressure in the equalizing reservoir 3 increases, the relay valve device of the brake valve 6 operates to effect the supply of fluid under pressure from the main reservoir 2 to the brake pipe 5 in the manner explained in hereinbefore-mentioned U.S. Pat. No. 2,958,561.

As pusher member 52 having slot 133 therein against the left-hand end of which rests pin 134 is moved in the direction of the right-hand in response to clockwise rotation of the cam 23 to its release position, it can be seen from FIG. 2 that the lever 130 is rocked counterclockwise about pin 139 to effect, via pins 131 and 128 and link 127, counterclockwise rocking of arms 117, 116 and 111, hollow rod 87 and hub 112 about pin 113 to thereby move movable contact 83 into circuit closing engagement with release contact 89. This establishes the hereinbefore-described power supply circuit to the solenoid of the release magnet valve device 11 on the locomotive and each car in the train whereupon these magnet valve devices operate to effect the supply of fluid under pressure to the brake pipe 5 so that fluid under pressure is now simultaneously supplied to the brake pipe 5 by these magnet valve devices 11 and the relay valve device of the brake valve 6.

As hereinbefore stated, the mechanical linkage 22 provides that operation of the control valve unit 20 leads operation of the magnet valve devices and 11. Accordingly, it should be understood that the supply valve 54 is unseated from its seat 51 for example, 0.002 inch at the time the movable contact 83 is moved into circuit closing contact with the release contact 89 to cause operation of the release magnet valve devices 11 to effect the supply of fluid under pressure to the brake pipe 5. The relay valve device of the brake valve 6 will continue to effect the supply of fluid under pressure to the brake pipe 5 until the supply valve 54 is moved into seating contact with its seat.

Referring to FIGS. 2 and 3, it will be seen that as the rod 79 is moved in the direction of the right hand in response to the flow of fluid under pressure to chamber 42 in the manner hereinbefore explained, the lever 141 is rocked clockwise about pin 146 to, via pin 142, shift link 138 in the direction of the right hand. This shifting oflink 138 in the direction of the right hand is effective via pin 139 to effect rocking of lever 130 clockwise about pin 134 which rests against the left-hand end of slot 133. Accordingly, as lever 130 is thus rocked clockwise about pin 134, it is effective, via link 127 and pins 128 and 131, to rock arms 117, 116, and 111, hub 112 and hollow rod 87 clockwise about pin 113 to move movable contact 83 out of circuit closing contact with stationary contact 89 to open the power supply circuit to the release train wire 8 and the solenoid of the release magnet valve device 11 on the locomotive and cars in the train. Upon this deenergizing the solenoid of these release magnet valve devices 11, they operate to terminate the supply of fluid under pressure therethrough to the brake pipe 5.

When the relay device of the brake valve 6terminates the supply of fluid under pressure to the brake pipe 5 in response to movement of the supply valve 54 into seating contact with its seat 51 after the release magnet valve devices 11 operate to cut off flow to the brake pipe, it is fully charged to the desired normal pressure carried therein. It will be understood that the brake control valves on the locomotive and cars in the train operate in response to charging the brake pipe 5 to the desired normal pressure carried therein to effect a release of the brakes on the entire train and recharging of the train brake equipment to the pressure carried in the brake pipe.

Referring to FIG. 2 of the drawings, it will be noted that the release contact 89 is carried at one end of a lever 91 the opposite end of which is normally biased by the conical spring 104 against the end of the set screw 102. Accordingly, it can be seen that, should the movable contact 83 strike the release contact 89 with sufficient impact to overcome the yielding resistance of the spring 104, the release contact 89 and lever 91 will be rotated counterclockwise about pin 95 to prevent damage to the release contact.

it can be seen from FIG. 2 that the application contact 107 is similarly mounted on the spring biased lever 91a to prevent damage to this contact.

As hereinbefore stated, the supply valve 54 is unseated from its seat 51 for example, 0.002 inch at the time the movable contact 83 is moved into circuit closing contact with the release contact 89. Accordingly, it will be understood that the self-lapping control valve unit 20 is operative to maintain brake pipe pressure against limited brake pipe leakage without operation of the release magnet valve devices 11 on the locomotive and cars thereby preventing wear of these valve devices and also pitting or burning of the contacts 83 and 89 which would occur if these contacts were opening and closing at a comparatively rapid rate.

It should be further noted that an engineers brake valve 6 provided with the combined pneumatic self-lapping control valve unit and master controller switch device 18 may be used to control operation of an electro-pneumatic straight-air railway train brake system by connecting the wire 94 to the application train wire and the wire 109 to the release train wire.

It should be remembered that in a conventional electropneumatic straight-air railway train brake system the application magnet valve device is connected between the application train wire and the return train wire, and the release magnet valve device is connected between the release train wire and the return wire.

Furthermore, the pipe 61 is connected to the straight-air pipe rather than to the equalizing reservoir, as shown in FIG. 1. Also, it should be noted that while the handle 19 of brake valve 6 occupies its release position, the exhaust valve 56 must be unseated from its seat 36 in order that no fluid under pressure is present in the straight-air pipe and this pipe is open to atmosphere via pipe and passageway 61, chamber 58 (FIG. 3), ports 165, interior of counterbore 38, past unseated exhaust valve 56, bore 34, counterbore 35, ports 33, the interior of cover member 27 and ports 166 therein.

Accordingly, when an engineer's brake valve 6 provided with the combined pneumatic self lapping control valve unit and master controller switch device 18 is used to control operation of an electro-pneumatic straight-air railway train brake system, it is necessary to replace the cam 23 with another cam having a reversed rise, That is to say that the cam 23 is removed from the shaft 24, and then replaced with another can which, while the brake valve handle 19, which is also secured to shaft 24, occupies its release position, has a recess in its contour in which the roller 71 is disposed. When the roller 71 is thus disposed in this recess, the spring 74 is rendered effective via spring seat 73 to move the exhaust valve 56, supply valve stem 54a and supply valve 54 to a position in which the exhaust valve 56 is unseated from its seat 36. It should be understood that the strength of the spring 55 is such that at this time it is effective to maintain the supply valve 54 seated on its seat 51 and therefore, the plunger member 52 in a position in which the pin 134 is positioned in the slot 133 in the plunger 52 intermediate the ends of this slot and at a distance from the left-hand thereof such that as the shaft 24 and the cam which has replaced the cam 23 are rotated by the handle 19 sufficiently to cause the roller 71 to ride up out of the recess in this cam and thereby move the plunger 52, supply valve seat piston member 43 having supply valve seat 51 formed thereon, spring 55, supply valve 54 and exhaust valve 56 in the direction of the right hand, as viewed in H6. 3, until the exhaust valve 56 is seated on its seat 36, the pin 134 will abut the lefbhand end of the slot 133. In other words, the exhaust valve 56 is seated on its seat 36 before any movement is imparted to the linkage 22 to cause this linkage to operate to effect movement of the movable contact 83 into circuit closing contact with the stationary 89 thereby establishing the power supply circuit to the solenoid of the magnet valve devices on the locomotive and cars in the train to cause operation thereof to effect the supply of fluid under pressure to the straight-air pipe.

If desired, the two above-mentioned cams can be combined into a single cam with the operating cam surface for automatic brake operation arranged arcuatcly from the operating a cam surface of straight-air brake operation. Accordingly, when such a cam is used for automatic brake operation, it will be mounted on the shaft 24 in such a position that, while the brake valve handle 19 occupies its release position, the roller 71 will contact the highest point on the cam surface for automatic brake operation, that is to say the point most remote from the axis of the shaft 24. On the other hand, when this cam is used for straight-air brake operation, it will be mounted on the shaft 24 in an inverted position such that while the brake valve handle 19 occupies its release position, the roller 71 will contact the lowest point on the cam surface for straight-air brake operation, that is to say the point on this cam surface that is nearest to the axis of the shaft 24, or in other words the roller 71 will be disposed in the above-mentioned recess in this cam.

Having now described the invention, what we claim as new and desired to secure by letters patent, is:

1. An electro-pneumatic brake control apparatus for a train having a locomotive and at least one car, comprising:

a. a train pipe, variations of the fluid pressure in which are effective to control brake applications and brake releases on the train,

b. a source of fluid on the locomotive at a pressure in excess of the maximum pressure in said train pipe, and on said at least one car at a pressure equal to said maximum pressure in said train pipe,

. a electroresponsive valve means on the locomotive and on each car respectively operative to effect the supply of fluid under pressure from said respective source to said train pipe, and the release of fluid under pressure from said train pipe to atmosphere,

d. first switch means on the locomotive operative to effect energization of all of said electroresponsive valve means to cause an increase of pressure in said train pipe,

second switch means on the locomotive operative to effect energization of all of said electroresponsive valves means to cause a reduction of pressure in said train pipe, wherein the improvement comprises,

f. a self-lapping fluid pressure control valve means on the locomotive for effecting variations of pressure in said train pipe,

g. a mechanical linkage for selectively operating said switch means, and

h. interlocking means so connecting said mechanical linkage to said control valve means for operation thereby that operation of said control valve means to effect variations of pressure in said train pipe leads operation of said switch means to cause said electroresponsive valve means to effect variations of pressure in said train pipe.

2. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve means comprises movable abutment means subject in opposing relation to a fluid pressure corresponding to that in said train pipe in a chamber at one side thereof and to the force of a control spring at the opposite side, said abutment being operatively connected to said linkage and shiftable in one direction, upon the fluid pressure in said chamber increasing to a value sufficient to compress said control spring, to cause saidlinkage to effect opening of one of said switch means, and shiftable in an opposite direction, upon the fluid pressure in said chamber decreasing to a value insufficient to maintain said control spring compressed, to cause said linkage to effect opening ofthe other of said switch means.

3. An electro-pneumatic brake control apparatus, as recited in claim 2, further characterized in that said control valve means comprises valve means operatively connected to said linkage and operable to effect the supply of fluid under pressure from said source of fluid to said chamber prior to operation of said linkage to effect closing of one of said switch means, and operable to effect the release of fluid under pressure from said chamber prior to operation of said linkage to effect closing of the other of said switch means.

4. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for effecting operation of said valve means.

5. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for effecting operation of both said valve means and said linkage.

6. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for so effecting operation of said valve means and said linkage that initial operation of said valve means occurs prior to initial operation of said linkage.

7. An electro-pneumatic brake control apparatus, as recited in claim 6, further characterized in that said means comprises:

a. a rotatable cam the rotation of which effects operation of said valve means, and

b. a pivotal connection between said valve means and said linkage.

8. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve means is effective to control variations of pressure in said train brake pipe notwithstanding failure of said mechanical linkage to selectively operate said switch means to cause said electroresponsive valve means to effect variations of pressure in said train pipe.

9. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized in that said linkage comprises:

a. a first link,

b. a pair of levers pivotally connected at one end to the respective opposite ends of said first link, one of said levers also being operatively connected intermediate its ends to said valve means, and the other of said levers also being operatively connected intermediate its ends to said movable abutment,

. first link means operatively connecting said first and second switch means to the other end of said one lever for effecting selective operation of said switch means,

d. biasing means operatively connected to said first link means for normally biasing one of said switch means toward an open position and the other of said switch means toward a closed position, v

e. a fulcrum member, and

. second link means operatively connecting said fulcrum member to the other end of said other lever.

10. An electro-pneumatic brake control apparatus, as

recited in claim 1, further characterized in that said first and second switch means each comprise:

a. two contacts,

b. means for simultaneously rocking one contact of each of said switch means in one direction or in an opposite direction,

. a pair of pivotally mounted levers at one end of which are respectively mounted the other contact of said switch means,

(1. a pair of spaced-apart stops for each of said levers, and

e. a pair of biasing springs each effective to normally bias a corresponding one of said pair of levers against one of said stops for the respective lever,

. each of said levers being rockable against the yielding resistance of the corresponding biasing spring into abutting relationship with the other of said stops for the respective lever in response to a hammer blow delivered to the contact mounted on said respective lever by the corresponding other contact of the respective switch means.

11. An electro-pneumatic brake control apparatus, as recited in claim 9, further characterized in that the other of said levers intermediate its ends is pivotally connected to one end of a movable member the opposite end of which is provided with a collar, and a spring means is effective to bias said collar into abutting contact with said movable abutment thereby providing an impositive connection therebetween.

12. An electro-pneumatic brake control apparatus, as recited in claim 11, further characterized in that the strength of said spring means exceeds the strength of said biasing means.

13. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve comprises:

a. a supply valve, and

b. a release valve, each of said switch means comprising:

c. a stationary contact, and d. a movable contact, and said linkage comprises:

e. a plurality oflinks, and

f. a plurality of levers, one of which carries said movable contact of each of said switch means,

g. the length of said links and said levers being so selected as to provide that the movement of said movable contacts exceeds the movement of said valves.

14. An electro-pneumatic brake control apparatus, as recited in claim 13, further characterized in that the length of said links and said levers may be so selected as to provide that the movement of said movable contacts exceeds the movement of said valves by a preselected ratio.

15. An electro-pneumatic brake control apparatus, as recited in claim 11, further characterized in that said imposi tive connection between said movable abutment and said movable member provide for compression of said spring means upon the angular velocity of said other lever exceeding the linear velocity of said abutment.

16. An electro-pneumatic brake control apparatus, as recited in claim 9, further characterized by means for shifting said fulcrum member in one direction or in an opposite direction, and means for locking said fulcrum member against said shifting and unlocking said fulcrum member to provide for said shifting.

17. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said train pipe is a brake pipe charged to a normal chosen pressure to effect a brake release, a reduction from which chosen pressure effects a brake application to a degree corresponding to said reduction.

18. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said train pipe comprises a straight-air pipe an increase of pressure in which effects a brake application on the locomotive and cars in the train, and a decrease of pressure in which effects a brake release on said locomotive and cars.

19. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device comprising:

a. a self-lapping control valve unit provided with an operating plunger movable longitudinally from a predetermined position to effect operation of said valve unit to supply fluid under pressure in accordance with the degree of movement of said plunger out of its predetermined position, and with a movable abutment subject on one side to 4 said fluid under pressure supplied by said unit, b. two switch means each comprising two contacts operable from an open position to a closed position and vice versa, c. a mechanical linkage, one member of which carries one contact of each of said switch means, another member of which is operatively connected to said operating plunger, and a third member of which is operatively connected to said movable abutment, and d. a manually operated cam means rotatable in one direction to effect shifting of said plunger in a corresponding direction to cause operation of said selflapping valve unit to supply fluid under pressure and operating said linkage to cause operation of one of said switch means from its open position to its closed position, said abutment being operatively responsive to the fluid under pressure supplied to said one said thereof to operate, via said third member. said linkage to cause operation of said one switch means from its closed to its open position.

20. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said abutment is subject on its opposite side to the force of control spring means operatively connected to said third member, and said plunger is shiftable in an opposite direction by the fluid under pressure effective upon said one side of said abutment, in response to rotation of said cam means in a direction opposite said one direction, to cause operation of said selflapping valve unit to release fluid under pressure from said one side of said abutment, and by biasing means to operate said linkage to cause operation of said other switch means from open position to closed position, said control spring means being effective via said third member, upon said release of fluid under pressure from said one side of said abutment to operate said linkage to cause operation of said other switch means from its closed position to its open position.

21. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said manually operated cam means comprises a shaft and a cam carried thereby, said cam being reversible with respect to said plunger to correspondingly reverse the direction of shifting of said plunger when said cam means is so reversed.

22. A manually operated combinedl pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that initial operation of said self-lapping valve unit to supply fluid under pressure occurs prior to initial operation of said linkage to cause operation to said switch means.

23. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that rotation of said cam means in one direction is effective'to shift said plunger in a corresponding direction notwithstanding rupture of any member ofsaid linkage.

24. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 20, further characterized in that said mechani cal linkage comprises:

a. a first link,

b. a pair of levers pivotally connected at one end to the respective opposite ends of said first link, one of said levers also constituting said another member of said linkage and being operatively connected intermediate its ends to said operating plunger, and the other of said levers also constituting said third member of said linkage and being operatively connected intermediate its ends to said control spring means,

c. first link means operatively connecting said first and second switch means to the other end of said one lever for effecting selective operation of said switch means accordingly as said one lever is rocked in one direction or in an opposite direction,

d. biasing means operatively connected to said first link means for normally biasing one of said switch means toward its open position and the other of said switch means toward its closed position,

e. a fulcrum member, and

f. second link means operatively connecting said fulcrum member to the other end of said other lever.

25. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said two switch means each further comprise:

a. means for simultaneously rocking one contact of each of said switch means in one direction or in an opposite direction,

b. a pair of pivotally mounted levers at one end of which are respectively mounted the other contact of said switch means,

c. a pair of spaced-apart stops for each of said levers, and

d. a pair of biasing springs each effective to normally bias a corresponding one of said pairof levers against one of said stops for the respective lever,

. each of said levers being rocked against the yielding resistance of the corresponding bias spring into abutting relationship with the other of said stops for the respective lever in response to a hammer blow delivered to the contact mounted on said respective lever by the corresponding other contact of the respective switch means.

26. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 20, further characterized in that said control spring means comprises two coaxial concentric springs of unequal strength the force of both of which is effective on said opposite side of said abutment and the force of only the weaker of which is effective on said third member.

27. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 26, further characterized in that the strength of the weaker of said springs exceeds the strength of said biasing means.

28. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19 further characterized in that said selflapping control valve unit comprises:

a. a supply valve and seat therefor, and

b. a release valve and seat therefor, each of said switch means comprises:

c. a substantially stationary contact, and

d. a movable contact carried on said one member of said linkage, and

e. the length of the members of said linkage being so selected that the movement of said movable contacts exceeds the movement of said valves with respect to their respective seats.

29. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device as recited in claim 28, further characterized in that the length of the members of said linkage may be so selected as to provide that the movement of said movable contacts exceeds the movement of said valves with respect to their respective seats by a preselected ratio.

30. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device as recited in claim 24 further characterized by means for shifting said fulcrum member in one direction or in an opposite direction, and means for locking said fulcrum member against said shifting and unlocking said fulcrum member to provide for said shifting. 

1. An electro-pneumatic brake control apparatus for a train having a locomotive and at least one car, comprising: a. a train pipe, variations of the fluid pressure in which are effective to control brake applications and brake releases on the train, b. a source of fluid on the locomotive at a pressure in excess of the maximum pressure in said train pipe, and on said at least one car at a pressure equal to said maximum pressure in said train pipe, c. a electroresponsive valve means on the locomotive and on each car respectively operative to effect the supply of fluid under pressure from said respective source to said train pipe, and the release of fluid under pressure from said train pipe to atmosphere, d. first switch means on the locomotive operative to effect energization of all of said electroresponsive valve means to cause an increase of pressure in said train pipe, e. second switch means on the locomotive operative to effect energization of all of said electroresponsive valves means to cause a reduction of pressure in said train pipe, wherein the improvement comprises, f. a self-lapping fluid pressure control valve means on the locomotive for effecting variations of pressure in said train pipe, g. a mechanical linkage for selectively operating said switch means, and h. interlocking means so connecting said mechanical linkage to said control valve means for operation thereby that operation of said control valve means to effect variations of pressure in said train pipe leads operation of said switch means to cause said electroresponsive valve means to effect variations of pressure in said train pipe.
 2. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve means comprises movable abutment means subject in opposing relation to a fluid pressure corresponding to that in said train pipe in a chamber at one side thereof and to the force of a Control spring at the opposite side, said abutment being operatively connected to said linkage and shiftable in one direction, upon the fluid pressure in said chamber increasing to a value sufficient to compress said control spring, to cause said linkage to effect opening of one of said switch means, and shiftable in an opposite direction, upon the fluid pressure in said chamber decreasing to a value insufficient to maintain said control spring compressed, to cause said linkage to effect opening of the other of said switch means.
 3. An electro-pneumatic brake control apparatus, as recited in claim 2, further characterized in that said control valve means comprises valve means operatively connected to said linkage and operable to effect the supply of fluid under pressure from said source of fluid to said chamber prior to operation of said linkage to effect closing of one of said switch means, and operable to effect the release of fluid under pressure from said chamber prior to operation of said linkage to effect closing of the other of said switch means.
 4. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for effecting operation of said valve means.
 5. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for effecting operation of both said valve means and said linkage.
 6. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized by an equalizing reservoir connected to said chamber, and by means for so effecting operation of said valve means and said linkage that initial operation of said valve means occurs prior to initial operation of said linkage.
 7. An electro-pneumatic brake control apparatus, as recited in claim 6, further characterized in that said means comprises: a. a rotatable cam the rotation of which effects operation of said valve means, and b. a pivotal connection between said valve means and said linkage.
 8. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve means is effective to control variations of pressure in said train brake pipe notwithstanding failure of said mechanical linkage to selectively operate said switch means to cause said electroresponsive valve means to effect variations of pressure in said train pipe.
 9. An electro-pneumatic brake control apparatus, as recited in claim 3, further characterized in that said linkage comprises: a. a first link, b. a pair of levers pivotally connected at one end to the respective opposite ends of said first link, one of said levers also being operatively connected intermediate its ends to said valve means, and the other of said levers also being operatively connected intermediate its ends to said movable abutment, c. first link means operatively connecting said first and second switch means to the other end of said one lever for effecting selective operation of said switch means, d. biasing means operatively connected to said first link means for normally biasing one of said switch means toward an open position and the other of said switch means toward a closed position, e. a fulcrum member, and f. second link means operatively connecting said fulcrum member to the other end of said other lever.
 10. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said first and second switch means each comprise: a. two contacts, b. means for simultaneously rocking one contact of each of said switch means in one direction or in an opposite direction, c. a pair of pivotally mounted levers at one end of which are respectively mounted the other contact of said switch means, d. a pair of spaced-apart stops for each of said levers, and e. a pair of biasing springs each effective to normally bias a corresponding one of said pair of levers against one of said stops for the respective lever, f. each of said levers being rockable against the yielding resistance of the corresponding biasing spring into abutting relationship with the other of said stops for the respective lever in response to a hammer blow delivered to the contact mounted on said respective lever by the corresponding other contact of the respective switch means.
 11. An electro-pneumatic brake control apparatus, as recited in claim 9, further characterized in that the other of said levers intermediate its ends is pivotally connected to one end of a movable member the opposite end of which is provided with a collar, and a spring means is effective to bias said collar into abutting contact with said movable abutment thereby providing an impositive connection therebetween.
 12. An electro-pneumatic brake control apparatus, as recited in claim 11, further characterized in that the strength of said spring means exceeds the strength of said biasing means.
 13. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said control valve comprises: a. a supply valve, and b. a release valve, each of said switch means comprising: c. a stationary contact, and d. a movable contact, and said linkage comprises: e. a plurality of links, and f. a plurality of levers, one of which carries said movable contact of each of said switch means, g. the length of said links and said levers being so selected as to provide that the movement of said movable contacts exceeds the movement of said valves.
 14. An electro-pneumatic brake control apparatus, as recited in claim 13, further characterized in that the length of said links and said levers may be so selected as to provide that the movement of said movable contacts exceeds the movement of said valves by a preselected ratio.
 15. An electro-pneumatic brake control apparatus, as recited in claim 11, further characterized in that said impositive connection between said movable abutment and said movable member provide for compression of said spring means upon the angular velocity of said other lever exceeding the linear velocity of said abutment.
 16. An electro-pneumatic brake control apparatus, as recited in claim 9, further characterized by means for shifting said fulcrum member in one direction or in an opposite direction, and means for locking said fulcrum member against said shifting and unlocking said fulcrum member to provide for said shifting.
 17. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said train pipe is a brake pipe charged to a normal chosen pressure to effect a brake release, a reduction from which chosen pressure effects a brake application to a degree corresponding to said reduction.
 18. An electro-pneumatic brake control apparatus, as recited in claim 1, further characterized in that said train pipe comprises a straight-air pipe an increase of pressure in which effects a brake application on the locomotive and cars in the train, and a decrease of pressure in which effects a brake release on said locomotive and cars.
 19. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device comprising: a. a self-lapping control valve unit provided with an operating plunger movable longitudinally from a predetermined position to effect operation of said valve unit to supply fluid under pressure in accordance with the degree of movement of said plunger out of its predetermined position, and with a movable abutment subject on one side to said fluid under pressure supplied by said unit, b. two switch means each comprising two contacts operable from an open position to a closed position and vice versa, c. a mechanical linkage, one member of which carries one contact of each of said switch means, another member of which is operatively connected to said operating pluNger, and a third member of which is operatively connected to said movable abutment, and d. a manually operated cam means rotatable in one direction to effect shifting of said plunger in a corresponding direction to cause operation of said self-lapping valve unit to supply fluid under pressure and operating said linkage to cause operation of one of said switch means from its open position to its closed position, e. said abutment being operatively responsive to the fluid under pressure supplied to said one said thereof to operate, via said third member, said linkage to cause operation of said one switch means from its closed to its open position.
 20. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said abutment is subject on its opposite side to the force of control spring means operatively connected to said third member, and said plunger is shiftable in an opposite direction by the fluid under pressure effective upon said one side of said abutment, in response to rotation of said cam means in a direction opposite said one direction, to cause operation of said self-lapping valve unit to release fluid under pressure from said one side of said abutment, and by biasing means to operate said linkage to cause operation of said other switch means from open position to closed position, said control spring means being effective via said third member, upon said release of fluid under pressure from said one side of said abutment to operate said linkage to cause operation of said other switch means from its closed position to its open position.
 21. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said manually operated cam means comprises a shaft and a cam carried thereby, said cam being reversible with respect to said plunger to correspondingly reverse the direction of shifting of said plunger when said cam means is so reversed.
 22. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that initial operation of said self-lapping valve unit to supply fluid under pressure occurs prior to initial operation of said linkage to cause operation to said switch means.
 23. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that rotation of said cam means in one direction is effective to shift said plunger in a corresponding direction notwithstanding rupture of any member of said linkage.
 24. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 20, further characterized in that said mechanical linkage comprises: a. a first link, b. a pair of levers pivotally connected at one end to the respective opposite ends of said first link, one of said levers also constituting said another member of said linkage and being operatively connected intermediate its ends to said operating plunger, and the other of said levers also constituting said third member of said linkage and being operatively connected intermediate its ends to said control spring means, c. first link means operatively connecting said first and second switch means to the other end of said one lever for effecting selective operation of said switch means accordingly as said one lever is rocked in one direction or in an opposite direction, d. biasing means operatively connected to said first link means for normally biasing one of said switch means toward its open position and the other of said switch means toward its closed position, e. a fulcrum member, and f. second link means operatively connecting said fulcrum member to the other end of said other lever.
 25. A manually operated combIned pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19, further characterized in that said two switch means each further comprise: a. means for simultaneously rocking one contact of each of said switch means in one direction or in an opposite direction, b. a pair of pivotally mounted levers at one end of which are respectively mounted the other contact of said switch means, c. a pair of spaced-apart stops for each of said levers, and d. a pair of biasing springs each effective to normally bias a corresponding one of said pair of levers against one of said stops for the respective lever, e. each of said levers being rocked against the yielding resistance of the corresponding bias spring into abutting relationship with the other of said stops for the respective lever in response to a hammer blow delivered to the contact mounted on said respective lever by the corresponding other contact of the respective switch means.
 26. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 20, further characterized in that said control spring means comprises two coaxial concentric springs of unequal strength the force of both of which is effective on said opposite side of said abutment and the force of only the weaker of which is effective on said third member.
 27. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 26, further characterized in that the strength of the weaker of said springs exceeds the strength of said biasing means.
 28. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device, as recited in claim 19 further characterized in that said self-lapping control valve unit comprises: a. a supply valve and seat therefor, and b. a release valve and seat therefor, each of said switch means comprises: c. a substantially stationary contact, and d. a movable contact carried on said one member of said linkage, and e. the length of the members of said linkage being so selected that the movement of said movable contacts exceeds the movement of said valves with respect to their respective seats.
 29. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device as recited in claim 28, further characterized in that the length of the members of said linkage may be so selected as to provide that the movement of said movable contacts exceeds the movement of said valves with respect to their respective seats by a preselected ratio.
 30. A manually operated combined pneumatic self-lapping control valve unit and master controller switch device as recited in claim 24 further characterized by means for shifting said fulcrum member in one direction or in an opposite direction, and means for locking said fulcrum member against said shifting and unlocking said fulcrum member to provide for said shifting. 